/* * Licensed to the Apache Software Foundation (ASF) under one * or more contributor license agreements. See the NOTICE file * distributed with this work for additional information * regarding copyright ownership. The ASF licenses this file * to you under the Apache License, Version 2.0 (the * "License"); you may not use this file except in compliance * with the License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.apache.flink.core.io; import java.io.IOException; /** * A simple serializer interface for versioned serialization. * * <p>The serializer has a version (returned by {@link #getVersion()}) which can be attached * to the serialized data. When the serializer evolves, the version can be used to identify * with which prior version the data was serialized. * * <pre>{@code * MyType someObject = ...; * SimpleVersionedSerializer<MyType> serializer = ...; * * byte[] serializedData = serializer.serialize(someObject); * int version = serializer.getVersion(); * * MyType deserialized = serializer.deserialize(version, serializedData); * * byte[] someOldData = ...; * int oldVersion = ...; * MyType deserializedOldObject = serializer.deserialize(oldVersion, someOldData); * * }</pre> * * @param <E> The data type serialized / deserialized by this serializer. */ public interface SimpleVersionedSerializer<E> extends Versioned { /** * Gets the version with which this serializer serializes. * * @return The version of the serialization schema. */ @Override int getVersion(); /** * Serializes the given object. The serialization is assumed to correspond to the * current serialization version (as returned by {@link #getVersion()}. * * * @param obj The object to serialize. * @return The serialized data (bytes). * * @throws IOException Thrown, if the serialization fails. */ byte[] serialize(E obj) throws IOException; /** * De-serializes the given data (bytes) which was serialized with the scheme of the * indicated version. * * @param version The version in which the data was serialized * @param serialized The serialized data * @return The deserialized object * * @throws IOException Thrown, if the deserialization fails. */ E deserialize(int version, byte[] serialized) throws IOException; }